Roasted Portobello Sandwich

• 4 Ciabatta rolls
• 2 Tbs Butter,
• 2 Tbs Olive oil, plus extra for drizzling,
• 4 Large portobello mushroom caps,
• 1 Sweet or yellow onion, halved and sliced,
• 1 Package of goat cheese, such as chevre,
• Arugula,
• Balsamic vinegar,
• Salt & Pepper

1. Preheat the oven to 400 degrees.
2. Heat the butter and olive oil over medium heat in a large pan or skillet (avoid the nonstick ones if you can help it). Add the onions and turn the heat to medium-low. Cook, stirring INfrequently (that's right, just relax and let 'em do their thing) until the onions are a deep golden-brown color, approximately 20 minutes. Remove from the heat and set aside.
3. While the onions carmelize, clean the mushroom caps. On a cookie sheet, drizzle the mushrooms with olive oil, salt and pepper. Roast at 400 for 8 - 10 minutes until they have reduced in size a little bit and look "roasty toasty."
4. Slice the ciabatta rolls in half, drizzle 'em with olive oil and -lightly- toast 'em in the oven.
5. On each roll, layer a smear, slice, or dollop of goat cheese; carmelized onions; 1 portobello cap; and a fluff of arugula. Drizzle the arugula with balsamic vinegar and top with the next slice of ciabatta. You know, like a sandwich... Because we're making sandwiches here... Don't look at me like that.
6. I could eat these things all day.

rolls, butter, olive oil, portobello mushroom caps, sweet, goat cheese, arugula, vinegar, salt

Taken from www.epicurious.com/recipes/member/views/roasted-portobello-sandwich-50068362 (may not work)